A Diving certification or C-card is a document (usually a wallet sized plastic card) recognizing that an individual or organization authorized to do so, “certifies” that the bearer has completed a course of training as required by the agency issuing the card. This is assumed to represent a defined level of ability and knowledge in underwater diving. Divers carry a qualification record or certification card which may be required to prove their qualifications when booking a dive trip, hiring scuba equipment or filling diving cylinders.
Open Water Diver
Open Water Diver (OWD) is an entry-level full diver certification for scuba diving. Although different agencies use different names, similar entry-level courses are offered by all diving agencies and consist of a combination of knowledge development (theory), confined water dives (practical training) and open water dives (experience).
Advanced Open Water Diver
Advanced Open Water Diver (AOWD) is a scuba diving certification level provided by several diver training agencies, such as Professional Association of Diving Instructors (PADI), and Scuba Schools International (SSI). The equivalent course offered by National Association of Underwater Instructors (NAUI) is the Advanced Scuba Diver.
Rescue Diver is a scuba diving certification level provided by several diver training agencies, such as PADI, SSI, SDI, and NAUI, which emphasises emergency response and diver rescue.